Condition monitoring of mechanical equipment can be performed in a number of different ways, both with physical inspection and condition estimation based on measured parameters. Such condition monitoring is essential for many applications in order to identify a deteriorating condition before it leads to an actual fault or breakdown of the system. One such example is offshore drilling rigs where operational reliability is critical and faults can have significant consequences, both environmental and in terms of personnel safety. This in particular applies to equipment which is operated under harsh conditions (e.g., exposed to weather or in contact with substances such as drilling mud) and/or subject to irregular loads or repeated load variations.
The most common maintenance strategy is presently calendar based; i.e., equipment must undergo a full maintenance cycle at predefined times. This is costly, especially if the equipment cannot be inspected/serviced on site. Most of the cost is related to non-productive time caused by the mandatory service. Apart from the potential cost saving from performing maintenance only when needed, or from planning for maintenance at times that are convenient according to the rig's work plans, great savings can also result from condition monitoring and predictions based on the trend of condition indicators if early signs of deterioration can be used to prevent breakdown. A need to further improve known systems and techniques therefor therefore exists.